Tuesday, 21 October 2014

Royal command ...

Queen of Spain Fritillary (Issoria lathonia)


I. lathonia is an extremely rare immigrant and transient resident to the British Isles with the first recorded specimen coming from Gamlingay in Cambridgeshire in 1710. It was first noticed in numbers in 1818 and was seen every year until 1885 - with the highest total of 50 records in 1872. Since then, sightings are few and far between with an additional 42 records up until 1939. Between 1943 and 1950 an additional 75 records were added and, since then, there has again been a dearth of sightings with no sightings at all in some years. In 2009, 9 individuals were seen near the Sussex coast, including a sighting of a mating pair. Even so, there have been less than 400 sightings in total since it was first discovered. To date there have been just over 50 confirmed accounts from Sussex.

Although females have been seen egg-laying, neither larvae nor pupae have been found in the wild except in the Channel Islands, where larvae were found in 1950. Larvae were again found in 1951 and 1957. However, in 1945, 25 individuals were recorded at Portreath in Cornwall, suggesting that a migrant female had deposited her eggs in the vicinity and that this concentration of adults were her offspring.

The vast majority of UK sightings are from the south coast of England, with a fairly even spread from Cornwall to Kent. There are fewer records further north and several records from southern Ireland. It is believed that the presence of this species on our shores is dependent on individuals originating in northern France. Unfortunately, the number seen there is also decreasing due to loss of suitable habitat and this undoubtedly has a knock-on effect.

The sexes are similar in appearance, although the female is slightly larger, with a shorter, more rounded abdomen than that of the male and a more extended greenish hue around the basal area of the upperside wings; the black markings also tend to be more bold. The characteristic silver spots on the underside hindwings mean that this butterfly is unlikely to be confused with any other species. The four images all depict males.




References:


Hulme, N., 2010. Queen of Spain Fritillary in West Sussex - Evidence of breeding by The Queen of Spain Fritillary butterfly (Issoria lathonia Linn.) at Chichester, West Sussex in 2009. Sussex Butterfly Report (2009). Sussex Butterfly Conservation, Issue 2, Spring 2010, pp.12-17.
Pratt, C. R., 2011. Queen of Spain Fritillary. A Complete History of the Butterflies and Moths of Sussex. Peacehaven, East Sussex: Colin R. Pratt, 2, pp. 265-267.

Friday, 17 October 2014

Urban warrior ...

Kestrel (Falco tinnunculus)


A young male Kestrel waits patiently and watches …

Like many British birds of prey, gamekeepers heavily persecuted the Kestrel during the 19th century and numbers fell dramatically. Since then numbers have fluctuated considerably; a variety of reasons for this have been suggested, but they were certainly hit hard by the use of organochlorine pesticides in agriculture in the 1950s and 60s. Kestrel numbers probably recovered to such an extent in the late 1960s and early 70s that it became Britain’s commonest bird of prey. In Sussex, the county population was estimated at 600 pairs in 1964-67, a figure that was revised to 800-1150 pairs in 1980. Numbers nationally have since fluctuated, but appear to be falling once more, with numbers down by 30% during 1995-2011 and an 18% decline in southeast England during 1995-2010.

A beautiful bird and one that evokes fond childhood memories …

References:

Prevost, L., 2014. Kestrel. The Birds of Sussex. Thetford: British Trust for Ornithology (BTO) Books on behalf of the Sussex Ornithological Society, pp. 203-204.
Hope, C., 1996. Kestrel. Birds of Sussex. Sussex Ornithological Society, pp. 202-204.